Add a date stamp to a photo online, without uploading it
Drop a photo. The page reads the date the camera saved in the file and prints it, with the time, in a band under the picture, so nothing in the photo is covered. If the file has no date, you type one. Either way the stamp says where the date came from, "from photo file" or "typed", and that it was added later. Then you download the stamped JPEG. The original is not changed and never leaves your device.
What the stamp says, and why it says it
Every stamp made here has two short lines under the date: where the date came from and the words "stamp added later". That is deliberate. A date printed on a photo is just pixels; what makes it useful to the person reading it is knowing whether it was the camera's record of the moment or something typed in afterwards. "From photo file" means the page read the EXIF DateTimeOriginal field the camera wrote. "Typed" means you entered it. The page never prints today's date as if it were the capture date.
The band is drawn below the image, not over it, so no part of the picture is hidden. The output is a new JPEG; the original file on your device is untouched. The new file carries no EXIF of its own, because saving from a canvas produces a bare JPEG and this page does not re-attach the metadata, so keep the original if the metadata matters.
When this is enough, and when it is not
It is enough when you need a readable date on a photo you already have: a photo of a delivery, a wall, a meter, a car, that you will send to someone who will not open file properties. It is not a replacement for a stamp made at capture. A stamp added later can only repeat what the file said or what you typed; it cannot say what the phone's clock and GPS reported when the shutter fired, and it cannot add a street address or coordinates the file does not contain. For photos you will have to explain later, take them with a camera app that stamps at capture and records where each value came from — that is what Asof does on Android and iPhone, with the same "from photo file / typed" labels for gallery photos. The overview of every way to date stamp photos compares the options.
Questions people ask
Is my photo uploaded?
No. The page is plain JavaScript. The file is opened in your browser's memory, drawn onto a canvas, and saved back to your device. There is no server behind it that receives the file. The only other script on the page is Cloudflare Web Analytics, which counts visits without cookies; it never sees your photo. For HEIC photos, browsers other than Safari 17 and newer need a converter: the page then downloads one script file from asof.day (open-source heic-to, based on libheif) and converts the photo on your device.
Where does the date come from?
From the photo's EXIF DateTimeOriginal field, if the file has one, including the time-zone offset when the camera recorded it. If the file has no date, which is common for photos received through messaging apps or screenshots, the field is left for you to type and the stamp says "typed".
Can I put today's date on an old photo?
You can type any date, and the stamp will say "typed" and "stamp added later". The page does not pretend a typed date is the capture date, and neither should you when you send the photo.
Why does the stamp go under the photo and not in the corner?
So that nothing in the picture is covered: a corner stamp can hide a serial number, a crack or a house number. The band adds a few percent to the image height instead.
Does the downloaded file keep the original metadata?
No. Saving from a canvas produces a JPEG without EXIF, and this page does not add any back, so the stamped JPEG has no GPS, no camera model and no original date fields. Keep the original file alongside it.